In wireless communications, the need to arrange communications efficiently continues to grow with the increasing number of mobile devices that in turn require increasing bandwidth to transmit an ever increasing amount of data. In order to provide adequate data throughput to and from an end user having a mobile user equipment (UE) device, it may be desirable to dynamically change the amount of bandwidth allocated to a UE. The 3GPP standard (LTE) (3rd Generation Partnership Project, Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); (release 10), 06-2011) has developed a set of standards for assigning one or more component carriers to transmit data and control signals. Each component carrier spans a frequency block within a larger band that may be assigned for communications between the UE and another device, such as a base station within a cell. In many scenarios, multiple component carriers may be allocated to a UE for communicating data and/or control signals between the UE and base station.
As specified in the LTE-A standard, which is an evolution of the 3GPP LTE standard, each carrier is a component carrier that is able to transmit data, control signals, and control channel information. In particular, each component carrier can include a Physical Hybrid-ARQ Indicator Channel (PHICH) that acts as a transmission channel for information that confirms or requests the retransmission of blocks of data that are incorrectly received by the receiving device. Thus, the quality of data sent over any component carrier can be ascertained using a channel within that component carrier.
However, it is anticipated that in future LTE standards (beyond LTE Release 10), extra carriers (non-backward-compatible component carriers) may be defined that function primarily to transmit data, but may not include the full control functionality as specified for component carriers. It is with respect to these and other considerations that the present improvements have been needed.